Chaerephon ansorgei (Thomas, 1913)

Don E. Wilson & Russell A. Mittermeier, 2019, Molossidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 598-672 : 645

59.

Ansorge’s Free-tailed Bat

Chaerephon ansorgei

French: Tadaride d’Ansorge / German: Ansorge-Bulldogfledermaus / Spanish: Caerepon de Ansorge

Other common names: Ansorge’s Wrinkle-lipped Bat

Taxonomy. Nyctinomus ansorgei Thomas, 1913 ,

“Malange [= Malanje], North Angola.”

This species is monotypic.

Distribution. Widely from NE Ivory Coast E to Ethiopia and S through parts of E Africa, Zambia, and Zimbabwe to E South Africa (KwaZulu-Natal), with an isolated record from W Angola.

Descriptive notes. Head-body ¢.66-81 mm, tail 36-42 mm, ear 19-22 mm, forearm 43-51 mm; weight 15-23 g. Pelage of Ansorge’s Free-tailed Bat is dark grayish brown to chocolate-brown or reddish brown above, grizzled with white spots and paler below except on throat, which is blackish to brown, conspicuously darker and denserfurred than elsewhere; wings are light grey or reddish brown; there are no mid-ventral markings or white band on inner flanks. Upper lip has 6-7 well-defined wrinkles on each side and many spoon-hairs. Ears are pale gray to reddish brown, joined by flap of skin, reaching about halfway along muzzle when laid forward. Both sexes have interaural crest of dark hairs (c. 2 mm long); denser and more conspicuous in males. Tragusis very small and subquadrangular; antitragus is much larger and roughly trapezoid (widest at base). Skull is not particularly flattened. Anterior palate is slightly emarginated and basisphenoid pits are moderately developed. M? has third ridge more than one-half as long as second ridge. Chromosomal complement has 2n = 48 and FNa = 66 or 68.

Habitat. Dry woodland savanna in the vicinity of rugged hills and mountain ranges with rocky cliffs and precipices,at elevations of 400-2000 m.

Food and Feeding. Ansorge’s Free-Tailed Bats are aerial feeders. In Zimbabwe, diet comprised mostly Coleoptera, Trichoptera , and Lepidoptera .

Breeding. Female Ansorge’s Free-Tailed Bats give birth to one young at a time. In Zimbabwe there are two birth seasons, at the beginning and end of the rainy season (November to April).

Activity patterns. Ansorge’s Free-tailed Bats are nocturnal. Natural roost sites include narrow cracks in rocks, especially on cliff faces, but they also roost in the roofs of houses, and large colonies occupy the expansion joints in high-level bridges. They produce narrowband FM echolocation calls with a low peak frequency (19 kHz), narrow bandwidth (12 kHz), and long duration (15 milliseconds). Predators include owls.

Movements, Home range and Social organization. Ansorge’s Free-tailed Bats roost communally in small to medium-sized groups, which may number in the hundreds. Roosts may be shared with Spotted Free-tailed Bats ( Chaerephon bivittatus ), Lappeteared Free-Tailed Bats ( C. major ), and Malagasy Free-tailed Bats ( Tadarida fulminans ).

Status and Conservation. Classified as Least Concern on The IUCN Red List. In West Africa, overharvesting for food may be a threat.

Bibliography. Bouchard (2001a), Cotterill (2013i), Monadjem, Cotterill, Hutson et al. (2017a), Monadjem, Taylor et al. (2010).

Figures

On following pages: 61. Spotted Free-tailed Bat (Chaerephon bivittatus); 62. Long-crested Free-tailed Bat (Chaerephon chapini); 63. Gallagher's Free-tailed Bat (Chaerephon gallagheri); 64. Grandidier's Free-tailed Bat (Chaerephon leucogasten); 65. Lappet-eared Free-tailed Bat (Chaerephon majon; 66. Nigerian Free-tailed Bat (Chaerephon nigeriae); 67. Sao Tome Free-tailed Bat (Chaerephon tomensis); 68. Little Free-tailed Bat (Chaerephon pumilus);, 69. Russet Free-tailed Bat (Chaerephon russatus); 70. Seychelles Free-tailed Bat (Chaerephon pusillus); 71. Madagascar Free-tailed Bat (Chaerephon atsinanana); 72. Black-and-red Free-tailed Bat (Chaerephon jobimena); 73. Lesser Northern Free-tailed Bat (Chaerephon johorensis); 74. Wrinkle-lipped Free-Tailed Bat (Chaerephon plicatus); 75. Fijian Free-tailed Bat (Chaerephon bregullae); 76. Solomons Free-tailed Bat (Chaerephon solomonis); 77. Greater Northern Free-tailed Bat (Chaerephon jobensis).

Distribution. Widely from NE Ivory Coast E to Ethiopia and S through parts of E Africa, Zambia , and Zimbabwe to E South Africa (KwaZulu-Natal), with an isolated record from W Angola .